Chimney.



UNITED STATES PATENT OFFICE. I

CHIMNEY.

Specification of Letters Patent.

Patented May 8, 1906.

Application filed February 21,1903. Serial No. 144,499.

To all whom it may concern.-

Be it known that I, LOUIS SEPULcHaE, a subject of the King. of Belgium, residing at 267 Rue St. Lambert, Herstal, near Liege, Belgium, have invented certain new and useful Improvements in Chimneys for Central- Draft Oil-Lamps and I do hereby declare the following to be a full, clear, and exact description. of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The object of the present invention is to replace the usual draft-chimney and the eyescreen globe with its support of central-draft oil-lamps by a draft-chimney which also veils the flame and which is constructed in such a way as to considerably augment the lighting power of the lamps, and consequently a perfect distribution of the transmitted light is obtained on account of the exactly appropriate profile which this eyescreen chimney represents, giving to the flame its greatest expansion, and this profile assures, besides, a more complete combustion of the carbon.

The draft-chimney is an absolute necessity in central-draft oil-lamps, as otherwise only an extremely-smoky flame would be obtained. In order that the draft may bring to the flame the exact quantity of air required for efficiently supporting combustion in accordance with the diameter of the circular wick of the burner, a certain appropriate height is necessary for'the chimney and at the same time a sufficient area in cross-section for the passage and evacuation of the products of combustion. The, combination of these two elements secures the indicated purpose, whether it be that a relatively greater height is given in a chimney of relatively narrower cross-section or a relatively reduced height in a chimney of relatively greater cross-section. Such are the conditions of a good lamp-chimney, and such a chimney is indispensable to the working of central-draft lamps, and, further, an eyescreen is extremely useful on account of the excessive brightness of the flame, the violence of which is hurtful to the eyes; but the eye-screens in use are of very little utility, first, on account of the considerable loss of light which they cause in spite of their transparency and a so on account of their large size and the difficulties which they present in the handling and transportation of lamps, and it is necessary in order to support them around the burner and draft-chimney to provide a special support located around the gallery which carries the chimney. To combine these two necessary parts in a single and more efficacious appliance constituting an eye-screen and chimney combined for use with central-draft oil-burners is the object of the present invention. It is to be remarked from the first that the globes sur rounding gas-flames serve only as light-softeners and they create no draft, and, moreover, they are not necessary for the burning of combustibles under pressure, The eyescreen chimney hereinafter described gives (besides a strong draft, which is not found in the usual globes) quite a different effect with regard to the illuminating power of the lamp. The chimneys in transparent glass, which are usually employed and which expose the flame directly to the eyes, necessitate that the flame should be perfectly steady from the moment of lighting, as the least flickering will tire the eyes to an intolerable degree. That is Why these chimneys must surround the flame closely and why they are also appreciably contracted above and on a level with the flame in order to prevent the whirling of the air and gases from the moment of lighting up. In order to compensate for the excessive friction which is thus created against the walls of the chimney, one is obliged to give to these draftchimneys a great and unsightly height, and it follows that through the compulsory and excessive nearness of the flame the chimneys in clear glass are very likely to split, to break, or even sometimes to soften and deform through being half melted.

Now this invention provides, by way of compensation, a draft-chimney of a notably larger diameter than that of the ordinary transparent chimneys and of a proportionately smaller height. This chimney is made in milky-colored or opal glass, albatrine, or other analogous translucid material and in this way is made to also serve as a screen. If in these conditions the currents of air are not regular and the flame is slightly agitated during a short period, or even if it be continually oscillating and unsteady, such unsteadiness is a matter of indifference, as the chimney, owing to the nature of its material, its construction, and profile, prevents such unsteadiness of the flame from affecting the eyes.

The considerations which determine the diameter of the eye-screen chimney at the level of the flame are that the walls of .the chimney must be at least at such a distance that the outline or contour of the flame is invisible. The annexed drawings show three forms of an eye-screen chimney made in milky or opal glass in accordance with the present invention.

Figure 1 shows in plain lines the eyescreen chimney as well as the flame, which is globular or made to assume the form of a tu-- lip by the draft' The dotted lines represent, respectively, an ordinary chimney of clear glass and an ordinary eye-screen globe. Fig. 2 shows an eye-screen chimney where the flame is cylindrical instead of globular; and Fig. 3 an eye-screen chimney of larger diamiatefi", giving a more attenuated and uniform As can be seen from the drawings, the neck at the lower end of the chimney is engaged in the gallery as in ordinary lamps. Immediately above thisregion the chimney widens, as indicated at m n p, 'to such an extent that it is so far from the flame and of a diameter as will render the contour of the flameinvisible, and from this oint the chimney gradually narrows toward the top according to the desired profile. Where the flame is cylindrical, the region of the chimney immediately next to the flame remains approximately cylindrical for a suitable height in order to preserve a constant distance between the flame and the walls, appropriate, however to the variated intensity of the said flame at its different levels. These chimneys are provided with a top aperture 0, the size of which is increased proportionately with the diminution of height of the chimney, but which remains appreciably smaller than the top orifice of the eye-screen globes in ordinary use. This diminution in height, as in the ing to w represented types-Figs. 1 and 2, for instancemay be to the extent of as much as thirty per centfor the reasons explained in the introduction.

The surface of the translucid cover constituting a draft-chimney must be as much as possible resented to the directions accordl ich one desires the most light, and consistent with these desired directions the said surface approaches as near as possible to the flame without the latter being visible.

The new appliance, which is placed in the gallery of the burner like the ordinary chimneys, has a notably smaller diameter than the ordinary eye-screen globes. These ordinary globes receive and transmit the light, but with a considerable loss, first, on account of the necessarily considerable distance between their walls and the flame, then on account of the interposition of the glass chimney, which (however distinctly clear and free it may be from the usual veil of impurities deposited on its interior surface conse uent upon the nearness of the flame-surface de- 1 flects and considerably weakens the luminous rays insuch a way that the walls of these eyescreens being reached by no direct perpendicular ray nor by any non-attenuated ray and finding themselves most necessarily at toogreat a distance from the center of light are very imperfectly illuminated.

The material of which the combined article is made is neither diaphanous nor transparent, but only and simply translucent. It appears from the results of experimental tests that the transmission of light does not take place in a direction parallel to the incident rays, but (apart from a certain diffusion) the said transmission occurs perpendicularlyto the exterior surface. The elements of this surface then comport themselves like the elements of a luminous surface.- The light which traverses is not distributed there regularly; but it is diffused in such a way that the flame transforms the diffusing-envelop of this appliance into a luminous body similar to an incandescent mantle. Thus, as one can see from the represented profiles, I utilize this valuable property to convey the light directly to the points where it is particularly desired to be utilized or to any particular part of a room or the like. Indeed the two zones are clearly distinguished in each of my appliances. The first extends from the socket d to a point indicated by the line A B a little above the flame and presents a surface receiving only the perpendicular rays of the laterally-enveloped flame, and it is this zone in particular which is illuminated and gives out its light with the greatest intensity, enlarging suddenly in curvature. Starting from the socket d, it envelops the flame, but at just such a distance as, if lessened, would'render the flame visible by making the walls diaphanous or transparent, or at such a distance, Fig. 3, that the walls are made more diffusive, but less luminous. By this principal zone the perpendicularly-emitted light at the surface n m dis distributed downwardly and horizontallywith an intensity and profusion greatly exceeding that of a flame seen through a clear glass and a lamp-shade. The other zone above the flame is comprehended between the line A B, r

and the top aperture 0 of the chimney receives only incident rays which are directed obliquely upward. It is of importance that the walls of this part should be sufiiciently inclined from the vertical and toward the flame so that the diminution of the illuminosity (of which the maximin is at the belly, where the rays are perpendicular) is not too marked. The walls are inclined toward the top aperture, so as to present an opening compatible with good draft, and normally reflect the light from them toward the walls of the apartments without the intervention of the ceiling, which serves as a reflector when the lamp-chimney is made, as usual, of clear glass only or when a shade or globe is used having large opening or a decided inward curve at the top and which absorbs uselessly a great part of emitted light. A wide eye-screen, according to Fig. 3, may therefore be advantageously employed when an attenuated and more diflused light is required.

To sum up the new effect which the new substituted appliance attains with regard to the flame as a luminous source, first, through the softening resulting through the emission of the light from a larger surface it takes advantageously the place of the usual globe complicated with a support and with a glass; secondly, through its own mode of transmission of'light perpendicularly to its surface it takes advantageously the place of the usual lamp-shade complicated with its support and a glass thirdly, through the disposition of its walls at the point where the outline of the inclosed flame is rendered invisible the illuminated appliance resembles, without a glaring brilliancy likely to injure the eyes, an enlarged mantle with a superior lighting power, these improvements being due to the improved combustion and to the better direction of the light as compared with the case of a naked flame and a clearglass chimney. Besides, the invention avoids the frequent breakages which occur with chimneys of clear glass, due to the contraction and to the closeness with which they usually surround the flame, while nevertheless the purchase-price of the combined article is appreciably less than that of the three separate articles which it practically takes the place of.

I claim An eye-screen chimney for lamps having an annular wick, and a central air-current, made entirely of a translucent material, and outlined in such away that its lower part, which immediately surrounds the flame, shall be parallel to the contours of this latter, while the upper part shall narrow gradually in a cone toward the top, that is to say toward the evacuation-orifice.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

LOUIS SEPULOHRE. lVitnesses.

VICTOR S. LAMAL, LOUIS BUPZ. 

